How to evolve regulation with technologies for the effective spectrum management

New radio technologies, such as those for the evolution of wireless broadband communications towards 5G, raise ever increasing challenges in assessing interference between different users concurring for the use of spectrum, and in defining proper strategies and future-proof rules to access airwaves. This paper highlights the role of the European Communications Committee (ECC) of the European Conference of Postal and Telecommunications Administrations (CEPT) to develop and propose common policies in Europe, that allow opening up the spectrum and accommodating new wireless uses, while ensuring protection of systems from harmful interference. The importance of relying on proper modelling for coexistence assessment is recalled, in particular with reference to the role of transmitters and receivers when new Active Antenna Systems (AAS) for 5G are concerned. The paper finally presents a study performed with the SEAMCAT simulator, to assess the interference generated from IMT-2020 mobile onto the Earth Exploration-Satellite Service space-to-earth data relay receiving earth station at 26 GHz.